Field of the Invention
This invention pertains to the oral feeding of infants when they are bottle fed.
Description of Related Art
Feeding with a feeding bottle has for the infant risks of suffocating, choking or liquid going down the wrong way, when the rate or the pressure of the liquid flowing through the teat is too high. The goal of this invention is to optimize infant safety, efficiency, and comfort. Safe and efficient oral feeding relates to the proper transport of food from the mouth to the stomach. For infants, this requires appropriate suck, swallow, and respiratory functions and implies proper neuromotor coordination of the different musculatures implicated in these three functions and, very importantly, their ability to “work together” in a temporal synchrony to avoid adverse events, e.g., risks of suffocating, choking, and liquid going down to the lungs.
For the majority of infants born term with mature neurophysiologic and neuromotor functions, nutritive sucking is a natural reflexive behavior. Unfortunately, for those whose skills are not sufficiently developed to engage in such activity, e.g., some term infants, infants born prematurely, or infants with congenital or medical anomalies, bottle feeding is not without risks. This not only puts infants at risk of adverse events as mentioned above, but also raises the risk for failure to thrive and/or prolonged oral feeding aversion.
The capacity of an infant to feed effectively and without risk depends on its ability to coordinate the steps of sucking, deglutition and respiration, as well as its sucking force. Although the majority of full-term babies are able to control and adjust the force and the duration of their sucking in order to maintain an acceptable rate of liquid transfer as a function of their capacity to coordinate the three aforementioned steps, this is not the case for a few of them, in particular in the event of fatigue, and for the majority of premature babies or infants with chronic conditions.
Bottle feeding is unsafe when the flow rate out of the bottle through the teat (nipple) is too fast for infants to handle because they cannot suck, swallow, and breathe safely at the same time. The development of nutritive sucking in infants is poorly understood, and, consequently, so are the causes of their oral feeding difficulties. If we do not understand the causes of such issues, can we, as caregivers, know how best to feed them? Nevertheless, bottle feeding is traditionally controlled by the caregiver (e.g., by controlling the angle of bottle inclination). Unfortunately, caregivers have no way of knowing the flow rate that a baby can handle, or the maturity of his/her nutritive sucking skills, and any difficulty can only be detected if the baby demonstrates overt signs such as choking, coughing, pulling away from the bottle, and/or turning blue due to lack of oxygen.
A person giving the feeding bottle has no way of knowing the flow rate that a baby is able to support and the sucking force that he/she is able to generate. However, this person is the only one in a position to control the rate of the liquid and not the infant. This flow rate depends in fact substantially on the hydrostatic pressure of the liquid at the outlet orifice of the teat of the feeding bottle, and therefore on the inclination of the feeding bottle in relation to the horizontal and to its level of filling. Faced with the uncontrolled flow of liquid flowing from a tilted feeding bottle, the infant can have difficulties getting his/her breath back or for resting, and as such runs the risk of suffocation, coughing, spitting, aspiration of liquid into the lungs and/or fatigue as his/her mouth is filling up with milk. Over time, the infant can develop an aversion for orality, or develop aspiration pneumonia due to the frequent penetration of liquid in the lungs. The higher the column of liquid over the nipple hole, the faster milk will drip out of a tilted bottle whether the infant is sucking or not. Therefore, to prevent passive milk drip, maintaining a substantially zero hydrostatic pressure over the nipple hole during feeding would be best.
Bottle feeding is also unsafe if it unnecessarily increases fatigue for the baby. With fatigue, an infant's oral feeding skills worsen. Also, coordination of sucking, swallowing, and respiration deteriorates, further increasing risks for adverse events. As the bottle empties during a feeding session, the internal negative pressure within the bottle or vacuum naturally increases, thereby hindering liquid outflow from the bottle as babies are sucking. Indeed, they must generate a greater sucking force to first overcome such resistance before they can get milk. This unnecessarily increases their energy expenditure and fatigue.
Finally, bottle feeding can put undue hand and wrist strain onto caregivers who need to frequently feed babies, such as mothers and hospital caregivers. Based on the poor shapes of many bottles, caregivers often need to maintain a tight grip on the device to ensure a good hold of the bottle and control of the feeding. This often leads to caregivers' discomfort, hand/wrist strain, and fatigue at feeding sessions.
Conventional feeding bottles often have a wider base and a narrower top, so that they are stable when resting in a vertical position on the table, full of liquid. To minimize milk drip with such a “bottom heavy” shaped bottle, a caregiver has to tilt the bottle at larger angles to achieve a substantially zero hydrostatic pressure (0 HP) than a bottle that is optimized to minimize the amount of tilting required to achieve 0 HP.
Also, in conventional bottles, the wider base concentrates more of the liquid at the rear of the bottle, which requires the caregiver to hold more tightly onto the bottle, creating more hand fatigue. For example, those conventional bottles cannot rest stably unaided on an open palm of a hand, even when full of liquid.
Also, many common bottles have recesses in the bottle's sidewall that are designed and optimized for a baby's grip. These recesses are generally not optimized for a caregiver's hand, which can lead to greater hand fatigue.
Finally, in some conventional bottles the angle that the nipple's centerline makes with the longitudinal central axis of the bottle is sometimes made greater than zero (e.g.)+25°. As infants are customarily fed in a semi-reclined position (approximately 30° from the horizontal plane), positioning the nipple at 90° to the plane of the lips (which is optimal for feeding) places the bottle in a nearly vertical position. This results in a large hydrostatic pressure because of the large height of the liquid's free surface above the nipple's outlet orifice, leading to greater dripping.
In summary, conventional feeding bottles have numerous problems that can significantly impair infants' bottle feeding performance; namely, (1) the presence of a positive hydrostatic pressure over the nipple opening that leads to inappropriate and unsafe milk dripping, (2) the creation of an internal vacuum build-up within the bottle as it empties that hinders milk outflow when babies are sucking, (3) caregivers' discomfort resulting from the sustained grasp they must have on the bottle in order to maintain control over the baby's feeding, and (4) inappropriate angling of the nipple relative to the bottle's centerline leading to high hydrostatic pressures at the outlet orifice. These problems impair the ability of infants to control and self-pace their own feeding.
It is therefore desirable to give control of a feeding to the baby as he/she knows the rate of liquid flow that they can tolerate. It is therefore desirable to give infants control over the liquid flow rate through the teat using an ergonomic bottle that is comfortable for the caregiver. Against this background, the present invention was developed.